Microwave Synthesis and Characterization of SnO Nanocrystallites

A novel route was used to obtain tin monoxide nanocrystallite in oqueous media, using SnCl2.2H2O and HCl in presence of ammonia by microwave heating method. High purity powders of SnO nanocrystallites with crystallite sizes less than 10 nm have been synthesised by a solution process. It is noticed that amorphous precipitate of Sn2+ is crystallized with microwave heating.The SnO samples show excitonic peaks in the UV-Vis absorbance spectra which is absent in the SnO bulk sample. Blue shift up to ~288 nm corresponding to an energy gap of 4.3 eV is observed for particle size of ~7 nm. The appearance of these excitonic peaks for nanocrystallities SnO may be attributed to the conversion of band gap from indirect in bulk SnO to the direct band gap in nanocrystallines SnO.The products were characterized by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM).

Keywords:

SnO , Nanomaterials , Microwave–assisted synthesis , Semiconductors